1. Field of the Invention
The present invention relates to a printing apparatus including a drying unit for drying a printed sheet.
2. Description of the Related Art
It is known that a drying time is shortened by installing a drying unit dedicated to the apparatus in a printing apparatus of an inkjet system, and subjecting a sheet on which ink is applied (deposited) to forced drying. Japanese Patent Application Open-Laid No. 5-270100 discusses an apparatus that can obtain appropriate drying state by variably controlling heater temperature of the drying unit and sheet conveyance speed depending on an ink amount used for printing, or a duty per unit area.
In a printing apparatus, a conveyance control may be performed, in which a conveyance speed (a sheet conveyance amount per unit time) is varied, even when print execution in one print job is in progress. Then, a conveyance speed of a sheet which passes through the drying unit is also varied in synchronism therewith. If an amount of heat of the drying unit is constant per time, heating amount is varied from area to area of the sheet resulting from variations of passing speeds through the drying unit of the sheet, and thus there is a possibility that an uneven drying may occur. The uneven drying may be visually identified as a color unevenness of an image.